---
category: Validator
created: '2021-04-10'
title: Check if a string is a MongoDB ObjectId
updated: '2021-10-13'
---

**JavaScript version**

```js isMongoId.js
const isMongoId = (str) => str.length === 24 && /^[A-F0-9]+$/i.test(str);

// Or
const isMongoId = (str) => str.length === 24 && str.split('').every((c) => '0123456789ABCDEFabcdef'.indexOf(c) !== -1);
```

**TypeScript version**

```ts isMongoId.ts
const isMongoId = (str: string): boolean => str.length === 24 && /^[A-F0-9]+$/i.test(str);

// Or
const isMongoId = (str: string): boolean =>
    str.length === 24 && str.split('').every((c) => '0123456789ABCDEFabcdef'.indexOf(c) !== -1);
```
